Manchester City’s hopes of a seminal four-trophy season took a big blow Tuesday, as a bid for the biggest title among them, the UEFA Champions League crown, now looks like one tough, uphill slog.

Leo Messi scored from the penalty spot early in the second half, having created the opportunity himself and put the home team a man down for 35 minutes in a match-turning (most likely even a series turning moment) moment that was quintessential Messi, an arresting dribbling burst.

Dani Alves’ 90th minute goal from a tough angle was certainly significant, too, putting this battle of giants further out of reach for the English club.

Barca’s 2-0 win Tuesday at the Etihad Stadium leaves the La Liga giants well in control of the teams’ Round-of-16 two-leg series.

In fact, this was the match of a Round-of-16 bunch, one that does come stocking stuffed with some other dandies. Barcelona controlled possession in a match with a “finals” feel, although the Citizens’ tactics were proving prescient for 50 or so minutes, as Manuel Pellegrini’s men made excellent use of the time on the ball they could wrestle from Tuesday’s visitors.

For Gerardo Martino’s Barcelona, criticized recently as the worst side from the Nou Camp in years, this win meant more than seizing control ahead of the return leg back in Spain. Barcelona had just one win in six Champions League matches on the road. Further, Martino’s club was winless in five away matches against English clubs.

Pellegrini raised eyebrows with the choice to deploy Aleksander Kolarov, usually a defender, in the midfield in front of Gael Clichy. Samir Nasri would surely have been the most attack-minded choice, although there are concerns that the French international is not fully fit. Also, the team was in more of a 4-4-1-1 rather than the more standard 4-4-2.

Most will excuse Pellegrini if those selections looked slightly on the conservative side – because his tactics did prove correct. While Barca generally held a big edge in possession, real scoring chances were quite few and City goalkeeper Joe Hart was mostly a spectator before the break.

Meanwhile, City refused to be stretched, perhaps occasionally frustrated by the inability to get the ball (or even get close to it, sometimes) but breaking with real authority when gaining control. David Silva found Alvaro Negredo with an early ball right down the middle for City’s first chance, following 18 minutes of almost all Barca possession.

When the home side wasn’t going direct, they aimed crosses for Negredo, generally looking to exploit one of their big edges in this compelling series: in size.

That’s not to say things were all that rotten for Barca, whose ability to keep the ball was a confidence builder and a tactically sound bit of its own, even if it did all look a bit punchless at times.

Messi’s moment broke open the stalemate in the 53rd minute as Barcelona won a ball along its let side. More accurately, City winger Jesus Nevas lost the ball and may have been fouled, although it looked more likely he was attempting to cover for a poor dribbling choice by throwing himself to the ground.

Either way, Andres Iniesta spotted Messi, who had quickly worked himself into the gap between City’s center backs. Iniesta zipped a ball into Messi’s path and the trailing (and slightly out of position) Martin Demichelis, probably the weak link along the Citizens back line, was in big trouble.

When Demichelis lunged in a desperate bid to stop Messi just outside the penalty area, he instead fouled the wily Argentine. The initial contact appeared to take place just inches outside the penalty area, but the result wasn’t just a spot shot – his sending off as the last man on a scoring opportunity left City a man down for more than half an hour.

Messi’s left-footer from the 12-yard spot went right down the middle, as Hart dove to his left. It was his 66th Champions League goal.

City did offer a reasonable account with just 10 men, creating some bother here and there; Silva’s stinger at the end of a swell City sequence was the best chance, forcing a fine 76th minute save from Victor Valdes. Still, Andres Iniesta, Cesc Fabregas, Alexis Sanchez and the other Barca attackers did more to keep Hart busy at the other end.